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	Influence of Blade Outlet Angle on Performance of Low-specific-speed Centrifugal Pump 期刊论文 OAI收割 JOURNAL OF THERMAL SCIENCE, 2013, 卷号: 22, 期号: 2, 页码: 117，122 Cui Baoling; Wang Canfei; Zhu Zuchao; Jin Yingzi 收藏 \| 浏览/下载：18/0 \| 提交时间：2013/04/27 centrifugal pump blade outlet angle numerical simulation external characteristic
	Trajectory tracking control of a quad-rotor UAV based on command filtered backstepping (EI CONFERENCE) 会议论文 OAI收割 2012 3rd International Conference on Intelligent Control and Information Processing, ICICIP 2012, July 15, 2012 - July 17, 2012, Dalian, China Gong X.; Bai Y.; Peng C.; Zhao C.; Tian Y. 收藏 \| 浏览/下载：30/0 \| 提交时间：2013/03/25 A quad-rotor unmanned aerial vehicle is an under-actuated strong coupled nonlinear system with parameters uncertainty and unknown external aerodynamic disturbance. The trajectory tracking control system with a nested double-loops structure is designed in this paper according to the coupling characteristic between the attitude angles and translational position. A PD control algorithm is proposed in the translational outer-loop to export the desired attitude signals to the attitude inner-loop. An adaptive backstepping control algorithm is designed in the inner-loop with respect to the uncertain rotational inertia and un-modeled disturbance while in order to reduce the computational complexity the command filtered approach is introduced into the designing procedure. And finally the numerical simulation results are presented for the trajectory tracking stabilization of a Quad-rotor which demonstrates the excellent performance of the proposed control system and illustrate its robustness in face of disturbance and uncertain parameters. 2012 IEEE.
	Robust trajectory tracking control of autonomous quad-rotor UAV based on double loop frame (EI CONFERENCE) 会议论文 OAI收割 2011 International Conference on Materials, Mechatronics and Automation, ICMMA 2011, January 15, 2011 - January 16, 2011, Melbourne, VIC, Australia 作者: Sun Q. 收藏 \| 浏览/下载：24/0 \| 提交时间：2013/03/25 This paper deals with the under-actuated characteristic of a quad-rotor unmanned aerial vehicle (UAV). By designing the double loop configuration the autonomous trajectory tracking is realized. The model uncertainty external disturbance and the senor noise are also taken into consideration. Then the H controller is put forward in the inner loop. An optimal stability augmentation control (SAC) method is used to stabilize the horizon position and keep it away from oscillation. By calculating the nonlinear decouple map control quantity is converted to the speeds of the four rotors. At last some simulation results and the prototype implementation prove that the control method is effective.
	Vertical-external-cavity surface-emitting lasers: Numerical simulation, and characterization (EI CONFERENCE) 会议论文 OAI收割 Optoelectronic Materials and Devices III, October 27, 2008 - October 30, 2008, Hangzhou, China 作者: Qin L. 收藏 \| 浏览/下载：26/0 \| 提交时间：2013/03/25 Firstly the vertical external-cavity surface-emiting lasers (VECSELs) device structure and model was given and the output characteristic was simple calculated. Then in experiment the VECSELs were grown bonded on to the heat sink and optically pumped by high-power 808nm diode laser array with fiber output module the light emission spectra were measured. Finally The thermal characteristic of the VECSELs was investigated by changing the temperature of the substrate. 2008 SPIE.
	Theoretical results of vertical external cavity surface emitting laser (VECSEL) (EI CONFERENCE) 会议论文 OAI收割 IRMMW-THz 2006 - 31st International Conference on Infrared and Millimeter Waves and 14th International Conference on Terahertz Electronics, Sep 18 - 22 2006, Shanghai, China 作者: Qin L. 收藏 \| 浏览/下载：13/0 \| 提交时间：2013/03/25 We calculate the characteristic parameters of 980nm infrared vertical external cavity surface emitting laser with the KP method and give the result of the relative longitudinal confinement factor threshold gain and output power. 2006 IEEE.
	Vertical-external-cavity surface-emitting lasers operating at different wavelength: Design, numerical simulation, and characteristics (EI CONFERENCE) 会议论文 OAI收割 Optoelectronic Materials and Devices for Optical Communications, November 7, 2005 - November 10, 2005, Shanghai, China 作者: Qin L.; Jiang H.; Wang L.; Wang L.; Wang L. 收藏 \| 浏览/下载：19/0 \| 提交时间：2013/03/25 We describe design numerical simulation and characteristics of high-power optical pumped VECSELs at different wavelength (980nm and 1300nm). The device design realizes the integrating diode-pumped lasers with vertical-cavity surface-emitting laser structure drawing on the advantages of both. With periodical gain element structure optical pumped VECSEL is scalable to watt level output. The characteristics such as threshold condition and output power are calculated theoretically. An optimum number of quantum wells and external mirror reflectivity are obtained from the calculation results and the thermal characteristic is also considered. Finally the calculation results also predict high output power in this kind of device structure.
	Theoretical analysis of 980nm high power Vertical External-cavity Surface-emitting Semiconductor Laser (VECSEL) (EI CONFERENCE) 会议论文 OAI收割 ICO20: Lasers and Laser Technologies, August 21, 2005 - August 26, 2005, Changchun, China 作者: Wang L.-J.; Wang L.-J.; Ning Y.-Q.; Qin L. 收藏 \| 浏览/下载：22/0 \| 提交时间：2013/03/25 By using bottom-emitting structure we will develop laser diode (LD) pumped 980 nm VECSEL with active region of InGaAs/GaAsP/AlGaAs system. Because the thickness of barrier layer and absorption layer exceed that of quantum well single well approximation model (KP method) can be used to calculate the band structure of VECSEL. The Schrodinger equation of finite deep potential well can be adopted to calculate the energy level structures of electron heavy and light holes. According to the transition selection rule we theoretically obtained the emitting wavelength of VECSEL and calculated quasi-Femi energy of valence band and conduction band based on the analysis of energy level structure of electron and holes. By analyzing the gain of strained quantum wells we calculated the gain of VECSEL using transition matrix elements of electron heavy and light holes. We give out the threshold gain output power and other characteristic parameters. We will study the configuration of VECSEL and pumping scheme. We designed external cavity mirror active region and bottom-emitting structure. A LD-pumped vertical external cavity surface-emitting laser whose output power is greater than 1.0 W can be predicted.